The present invention relates generally to solutions for providing nutrition to patients. More specifically, the present invention relates to amino acid solutions.
It is known to provide amino acids in parenteral solutions to patients. These solutions can be utilized for total parenteral nutrition (TPN). Examples of such solutions include 10%, 8.5%, 5.5%, and 3.5% Travasol.RTM. (amino acid) injection, with and without electrolytes, available from Clintec Nutrition Company, Deerfield, Ill.
It is also known to provide branched chain amino acids, i.e., isoleucine, leucine, and valine in parenteral solutions. An example of such a product is 4% Branchamin (branched chain amino acid) injection available from Clintec Nutrition Company, Deerfield, Ill.
For a variety of medical reasons, e.g., fluid restricted patients, it is desirable to have an amino acid solution for TPN that is as concentrated as possible. Of course, such a solution must have the appropriate nutritional balance. Likewise, for convenience reasons, e.g., volume of stock and transportation, it is desirable to have a TPN solution having as great an amino acid concentrated as possible.
Presently, the highest concentration amino acid solution for TPN that is available, to the best of the inventors' knowledge, is a 15% (wt/vol) solution. Although attempts have been made to provide higher concentrated amino acid solutions, these attempts have not been entirely successful.
One previous practice for attempting to develop an amino acid solution of increased concentration was to simply increase the amino acid components. However, this practice does not work when the components of a 15% formulation are increased proportionally. Merely increasing the amino acids proportionally will cause the amino acids to begin to precipitate out of solution.
One approach to attempt to solve this problem is to increase the total amino acid concentration by loading up the mixture with the amino acids that are most soluble. Using this method, conversely the less soluble amino acids are not increased in any significant amount. However, the result of this approach is an amino acid solution which, while perhaps more concentrated, is not nutritionally useful.
It is also desirable to have a solution that is highly concentrated in branched chain amino acids as well as amino acids. Presently, the only way to obtain such a solution is to admix a branched chain amino acid solution, e.g., 4% Branchamin.RTM., with another amino acid solution which has a broad amino acid profile, e.g., Travasol.RTM.. However, by so admixing a highly concentrated amino acid solution is not achieved. Further, a single stable solution that can be stored is not provided through this method.